Loud-speaker panel



Nam 30 9 3&2.

R. T. GRIFFETHS LOUD S PEAKER PANEL Filed April 8, 1925 2 h ts 1 mum-mNa y 3% 1926.

R. T. GRIFFITHS LOUD SPEAKER PANEL Filed April 8, 1925 2 Sheets-Sheet 2Patented Nov. 30, 1926.

UNITED STATES PATENT OFFICE.

RICHARD T. GRIFFITHS, OF AKRON, OHIO,

AssIGNoR To THE MILLER RUBBER com PANY, or AKRON, 01110, A CORPORATIONor OHIO. I a

LOUD-SPEAKER PANEL.

Application filed April 8,

My resent invention relates to improve ments 1n panels for use incabinets of the sound producing type, such for example as a cabinet thatis used for radio purposes,

and the invention aims to provide a panel which may be .built into orused for such cabinets, and which panel will have incorporated therein asound amplifier or horn, thus enabling the separate and unsightly hornswhich are now used for loud speaker purposes, to be dispensed with.

The invention comprises the novel construction hereinafter described anddefined by the appended claims.

An embodiment of my invention 'is illustrated in the accompanyingdrawings, in which Figural is a plan view of one face of the panelmember.

Fig. 2 is an edge view. 7

Figs. 3 and 4: are sectional views on lines 33 and Hrespectively of Fig,1.

Fig. 5 is a plan or face view of the covering plate which carries theloud speaker unit and horn bell.

Fig. 6 is an edge view of the plate of Fi 5.

ig. 7 is a sectional view showing the anal construction embodied in acabinet as the back wall thereof. A

Fi 8 is a similar view showing how the panemay be incorporated in anordinary cabinet, and

Fig. 9 is a detail view.

Referring by reference characters to these drawings, the numeral 1designates a pane member or late of molded material suitable for cabinetwork, as for instance, vulcanized hard rubber composition, which plate,of course, may be of any desired size and dimensions. In the molding ofthis plate, I form it with an elongated and ta red channel or recessindicated at 1, the walls of the recess being preferably substantiallyof the same thickness throughout, and

being conveniently, and as shown, of the same thickness as the plateitself, and of course, being integral therewith. This recess forms thesound amplifying chamber, and in order to get the desiredlength in amedium sized panel, I make the channel in the shape of a reverse curveas shown, thus providing two substantially parallel channel portions.The small end of the channel is roundedto merge with the plate and forma preferably tickened or 1925. Serial No. 21 646.

closed end for the channel, as indicated at 1", and the larger end issimilarly rounded.

view in Fig. 5, which referably has an outline of substantially t 1esame outline as the channel, but slightly lar er so as to rest againstthe flanges 1 an completely close the channel with the exce tion of thesmall and large ends thereof, w ich are left 0 en by reason of thecircular openings 2* an 2 formed in the plate 2. The portions of theplate carryin these openings 2 and 2 are 7 I rovided with flanges a andb respective y, which are ada ted to receive, the former the ordinarylou speaker unit (shown conventionally .at 3), and the latter, a bellmouth, indicated at 4. Theconnection of these parts may be made eitherby a threaded connection or a slip; joint, or otherwise, as desired. Theplate 2 is preferably provided with openings 0 1 which may be formed inears or projections 2, which 0 enings are adapted to re-.

1 formed on the late 1 a jacent the edges of i the channel. T e panelmember. may be provided at its edges with grooves 1 for forming a tongueand groove connection with the end walls of the cabinet, and with topand bottom edge flanges 1 to enter corresponding grooves in the top andbottom of the cabinet, as shown in Fig. 7. The front of the cabinet mayconsist ofthe ordinary work 5.

However, thedevice may i? unitary article in the back oan ordinarycabinet instead of being used to form the rearpanel or back wall of thecabinet, in which event the panel member 1" and plate 2" would form asupplemental back or spaced member.

Before assembling the two panel members, it is desirable to coat theadjoining edges with an adhesive cement such as rubbercegrill placed asa ment, whereby an air tight connection is secured.

Having thus described my invention, what I claim is 1. In combination, apanel member of molded material having a tapered cavity therein, and aclosure member therefor having circular openings corresponding to thelarger and smaller ends of said cavity.

2. A panel member of molded material having a tapered cavity therein,and a closure member therefor having circular openings corresponding tothe larger and smaller ends of said cavity, said smaller opening havingmeans for connecting a loud speaker unit.

'3. A panel member of molded material having a tapered cavity therein,and a closure member therefor having circular openings corres onding tothe larger and smaller ends of sai cavity, and a bell mouth elementconnected with said larger unit.

4. A panel member of molded material having a flaring channel thereinprovided with portions disposed substantially parallel to each otherwith the walls of the panel member and channel portion of equalthickness throughout,'and a closure member for the channel ofsubstantially the same thickness, said closure member having large andsmall openings coinciding with the respective ends of the channel.

5. A panel member having an elongated taperedchannel therein providedwith rounded end walls, and a closure member covering the channel andprovided with circular openings coinciding with the ends of the channeland conforming thereto in size.

6. A panel member for the back wall of a radio cabinet composed of hardrubber having a flaring channel formed therein and disposed lengthwisethereof, said channel having rounded ends, a closure member for saidchannel having openings coinciding with the ends of said channel, saidclosure member havin annular flanges encircling the openings t iereinfor attachment of a loud speaker unit and bell member.

In testimony whereof, I afiix my signature.

RICHARD T. GRIFFITHS.

